A type of attachment tool that is commonly used for the purposes of cutting away and clearing undergrowth and timber in forested areas is a bucket or shovel type attachment which employs forwardly extending tines in conjunction with an enclosed bucket or solid blade proper. Attachments of this type are inefficient in this environment in that much of the dirt, rocks and other unwanted material that is scrapped up along with the undergrowth and timber is trapped in the bucket or shovel proper and is carried along with the undergrowth and timber. This means that an increased number of trips must be made by the vehicle in each situation in order to properly clear the underbrush because the bucket or blade is prematurely filled with unwanted material. As well, the unwanted material adds to the bulk of a stockpile of undergrowth and timber which is built up. It is common when clearing land to burn the undergrowth and timber that is collected during the clearing process. If one uses a known tool attachment the foreign matter collected will hamper the burning action of the fire and may even extinguish the fire.
Another problem with the use of such attachments is that valuable topsoil is necessarily removed from the land when cleared or unevenly distributed on the cleared land.
The applicant has conducted a review of pertinent known apparatus within the field of the invention and has located the following references which disclose relevant equipment:
U.S. Pat. Nos. 2,070,964, Feb. 16, 1937, Scott et al., 2,612,280, Sept. 30, 1952, Stueland, 2,932,100, Apr. 12, 1960, Goethe, 2,950,551, Aug. 30, 1960, Pesce, 3,081,564, Mar. 19, 1963, Prater;
Canadian Pat. Nos. 543,725, July 16, 1957, Wagner, 616,626, Mar. 21, 1961, Wagner;
German Pat. No. 2,723,858, published Dec. 15, 1977.
Most of these references disclose material moving apparatus which employs a "pushing" action. The material is pushed in a direction away from the operator. Moreover, some of the apparatus disclosed is not capable of clutching or lifting the material being cleared.
West German Offenlegungsschrift No. 2,723,858 is prima facie pertinent because it shows a tined claw-like tool attachment. This document discloses an attachment that uses a shock-absorbing mechanism designed for working underground to scrape soil and the like from the walls of tunnels. The shock absorber is employed to prevent damage to the equipment when a rock or root or the like is encountered by the tines. The difficulty of this design when applied to cutting away and clearing undergrowth and timber is that the shock-absorber feature would prevent enough closing pressure being applied on the tines in order to properly hold the undergrowth and timber between the tines and the arm of the material moving apparatus.
As well, the hinging mechanism between the tines and the arm is not designed with lifting of material in mind but is designed to move in conjunction with the shock absorption device. The attachment is not hinged in locations which best permit material such as undergrowth and timber to be held or grasped. The placement of the hinges on the attachment prevents the tines from being moved to a fully closed position, thereby creating further difficulties. If smaller amounts of undergrowth or timber are to be held by the attachment, they will not be held as securely as is possible with an apparatus where the tines can be completely closed.